Unmanned aerial vehicles are continuing to increase in use. For example, unmanned aerial vehicles are often used for surveillance. There is also discussion of electronic-commerce retailers, and other entities, delivering items directly to a user's home using unmanned aerial vehicles. Unmanned aerial vehicles used by hobbyists often rely completely on receipt of control signals from a user-operated remote control device. Thus, these unmanned aerial vehicles rely on a user to provide most or all navigational instructions. More advanced unmanned aerial vehicles may determine some navigational instructions without direct input. These unmanned aerial vehicles may receive high level instructions (such as waypoints, a destination, and/or other parameters), and may implement logic to navigate through airspace based on the high level instructions and other information accessed by sensors on the unmanned aerial vehicles. With regard to the navigation, certain factors (e.g., changing weather, unexpected obstacles, etc.) may have varying levels of impact on the ability of some unmanned aerial vehicles to perform specified tasks, such as travelling along a predetermined route to deliver a package within an expected timeframe.
While implementations are described herein by way of example, those skilled in the art will recognize that the implementations are not limited to the examples or drawings described. It should be understood that the drawings and detailed description thereto are not intended to limit implementations to the particular form disclosed but, on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope as defined by the appended claims. The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include,” “including,” and “includes” mean “including, but not limited to.”